| ( | 287 | − | ( | 96 | + | 65 | + | x | ) | ) | ÷ | 2 | = | x |
| 方程左边 = | 287 | × | 1 2 | − | ( | 96 | + | 65 | + | x | ) | × | 1 2 |
| = | 287 2 | − | ( | 96 | + | 65 | + | x | ) | × | 1 2 |
| = | 287 2 | − | 96 | × | 1 2 | − | 65 | × | 1 2 | − | x | × | 1 2 |
| = | 287 2 | − | 48 | − | 65 2 | − | x | × | 1 2 |
| = | 63 | − | 1 2 | x |
| 63 | − | 1 2 | x | = | x |
| - | 1 2 | x | − | x | = | - | 63 |
| - | 3 2 | x | = | - | 63 |
| 63 | = | 3 2 | x |
3 2 | x | = | 63 |
| x | = | 63 | ÷ | 3 2 |
| = | 63 | × | 2 3 |
| = | 21 | × | 2 |
| x | = | 42 |